/* Reset cơ bản */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

/* Nền toàn trang */
body {
    font-family: Arial, sans-serif;
    background: linear-gradient(135deg, #89f7fe, #66a6ff);
    min-height: 100vh;
    display: flex;
    justify-content: center;
    align-items: center;
    padding: 20px;
}

/* Khung chính */
.container {
    background: white;
    max-width: 700px;
    width: 100%;
    padding: 40px 30px;
    border-radius: 20px;
    box-shadow: 0 10px 25px rgba(0, 0, 0, 0.15);
    text-align: center;
}

/* Tiêu đề chính */
h1 {
    font-size: 40px;
    color: #222;
    margin-bottom: 15px;
}

/* Đoạn mô tả */
.container > p {
    color: #555;
    font-size: 18px;
    margin-bottom: 30px;
}

/* Card nội dung */
.card {
    background: #f8f9fa;
    padding: 20px;
    margin: 15px 0;
    border-radius: 15px;
    box-shadow: 0 5px 15px rgba(0,0,0,0.08);
    text-align: left;
}

/* Tiêu đề card */
.card h2 {
    color: #007bff;
    margin-bottom: 10px;
}

/* Nội dung card */
.card p {
    color: #444;
    line-height: 1.6;
}

/* Footer */
footer {
    margin-top: 30px;
    color: #777;
    font-size: 14px;
}